feat: ship skill and MCP workflows with signed updater for v0.0.7

resources/updates/manifest-contract.md

@@ -0,0 +1,41 @@
+# YCode Update Manifest Contract v1
+
+The release tooling and updater backend use this exact document:
+
+```json
+{
+  "payload": {
+    "schemaVersion": 1,
+    "version": "0.0.2",
+    "publishedAt": "2026-10-20T10:00:00.000Z",
+    "notes": {
+      "zh": "更新说明",
+      "en": "Release notes"
+    },
+    "platforms": {
+      "windows-x64": {
+        "url": "http://192.168.10.6/ycode/releases/versions/0.0.2/YCode-0.0.2-Setup-x64.exe",
+        "size": 123456789,
+        "sha256": "64-lowercase-hex-characters"
+      }
+    }
+  },
+  "signature": "base64-encoded-64-byte-ed25519-signature"
+}
+```
+
+Rules:
+
+- The Ed25519 signature covers exactly `Buffer.from(JSON.stringify(payload), "utf8")`.
+- Payload property insertion order is part of the contract and must be preserved.
+- `publishedAt` is canonical UTC ISO-8601 with millisecond precision.
+- `version` is strict SemVer. Build metadata does not establish newer precedence.
+- `sha256` is lowercase hexadecimal; `size` is the exact installer byte length.
+- The artifact URL is absolute HTTP(S), has no query, fragment or credentials, and is exactly
+  `<base>/versions/<version>/<safe-installer-name>.exe`.
+- The client and release tooling require the artifact origin to match the manifest origin.
+- `latest.json` is served at `<base>/latest.json`; artifacts are immutable version directories.
+- `resources/updates/public-key.pem` is the SPKI PEM trust anchor. Private keys never enter the
+  repository, the server, build artifacts or logs.
+
+Default base URL: `http://192.168.10.6/ycode/releases/`

resources/updates/public-key.pem

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+-----BEGIN PUBLIC KEY-----
+MCowBQYDK2VwAyEAxUeHhwDpkjDtIDI9EliFgdmMjahN5Mgq/2cX2+gLkKY=
+-----END PUBLIC KEY-----